Phonograph pick-up



A ril 22, 1930. o. B. PARKER 1,756,012

' 'PHONOGRAPH PICK-U? Filed Jan. 7, 1929 m'vENroR ORNEY Patented Apr.22, 1930 UNITED STATES PATENT OFFICE.

OLIVER IB. PARKER, 01 NEW YORK, N. Y., ASSIGNOR TO PACENT ELECTRICCOMPANY, IN (7., OF NEW YORK, N. Y., A. CORPORATION OF NEW YORKPHONOGRAPE PICK-UP Application filed January 7, 1929. Serial No.330,764.

The objects of this invention are to provide an electric pickup forphonographs, which will be particularly simple, inexpensive, small andcompact, light in weight and well balanced, so as not to wear on therecord and in which the movable element will have a free butrelativelyshort movement.

Various other objects and the novel features of construction by whichthe same are attained will appear in the course of the followingspecification.

The drawing accompanying and forming part of the specificationillustrates one practical embodiment of the invention, but it should beunderstood that the structure may be modified as regards this disclosurewithout departure from the true spirit and broad scope of the invention.

Fig. 1 is a broken side elevation and part longitudinal sectional viewof the unit in its operative relation to the phonograph record; Fig. 2is a. broken plan view of the unit with the case removed and partsappearing in section; Fig. 3 is a detached detail view of. the

armature element of the'unit; Figs. 4 and 5 are detached plan views oftwo forms of resilient mounts for the armature.

The magnetic field is provided in the present disclosure by a small butrelatively powcrful permanent magnet 7 of the horseshoe type and aparticularly important feature of this magnet is that it is supported ina flat, substantially horizontal position, close to the record surfaceindicated at 8. The actual support is shown as a hollow arm 9, which issuitably pivoted so as to swing, and raise and lower relative to therecord, this arm carrying at its swinging end a plate or base 10 onwhich the U portion of the magnet is seated and to which it is suitablysecured as by means of a screw 11 passed up through the .base into aclamp plate 12 bridging the arms of the magnet. This provides aparticularly well-balanced low-lying structure.

For concentrating the magnetic flux, pole pieces of generally C-shapeformation are provided as indicated at 13 and the same are secured toand connected in magnetic relation with the U-magnet by brackets 14: 5of magnetic material secured to the arms of the magnet by screw bolts 15and to the pole pieces by screws 16. These brackets are shown in Fi 1 asangled to tilt the pole pieces away rom theend of the magnet, so as tobring the armature which operates between the pole pieces into aninclined or slanting position.

vThe armature which is designated 17 is shown as a short straight rod orpiece of magnetic material having a flattened and widened upper end 18disposed between the upper set of pole tips 19 and a heavier baseportion 20 disposed between the lower set of pole tips 21 and having ascrew seat 22 for the screw 23 which clamps the needle 24: in the lowerend of the same.

The armature is flexibly and resiliently mounted by means of a plate orstri 25, of material having the necessary flexibility and resiliency tocenter the armature and at the same time provide for the necessarymovements of the same. Bakelite, a phenol condensation product inflexible sheet form, has been found suitable for the purpose, it beingsuflicicntly stilf, but at the same time possessing enough flexibilityand resiliency. In the illustration, the base of the armature is shownas having a reduced portion 26 extended through a central aperture 27 inthe bakelite strip and riveted over the underside of the strip at 28 andthe strip is shown as supported in spaced relation from the lower armsof the pole pieces by spacing washers 29 and rivets 30. I

To render the central armature mounting portion of the bakelite piecesufiieiently re-' silient, the same may be cross-slotted as indicated at31 in Fig. 4, or the strip may simply be of relatively narrow orribbon-like construetion as shown in Fig. 5.

The thin bakelite plate or strip holds the armature properly centeredand controlled for the desired vibration movements relative to the poletips and at the same time acts as a brace tying the pole tips togetherin' spaced relation.

The winding is shown'as a single flat coil 32 supported in the hollowsof the C shaped pole pieces and having a bore large enough for the freemovement of the upper portion bled and of the armature. The armaturesupporting strip may be held by screws or the like instead of rivets toenable removal of the arigiture and dismounting when that is dei Thearrangement of the magnet in flat horizontal relation close. to therecord surface is particular]; advantageous, bringing the mass of weightdownclose to therecord and m enabling, the

use of 'a' short armature with a short stroke. The action is moreefiective electrically'and the structure is better mc-' chanicall Thedevice ma be easily assemause of its flat ow-l'ymg charac- 15 takes uless overhead room in the pho- -f"nographca inet. I

What is claimed is: y y '1. An electric phdnographpmkup, com- 1 risina'.U t pe magnet means for support-- 2 ibg 'tl e semi substantiallyhorizontal and close above a record surface, a short strai ht armaturebar, means for yieldingly mounting the same inclined downwardly" andaway from the ends of the magnet, a record engag- 25 ing stylus at'thelower end of end armature 'bar and'a coil about-the upper portion ofsaid armaturebar... j

- 2. An electric phonograph p1ckup, comprising a U-type magnet, meansfor supportso the same in substantially flat horizontal re ation, polepieces inclined downwa'rdly and 'away from the ends of saidsubstantially horizontal magne t,:a substantially straight across thetips of said pole" ieces and 'an armature bar mounted on said supportingstrip in co-operative relation to the ,pole pieces and the winding. v I

4. In apparatus of the character disclosed,

the combination of a magnet structure, a

winding carried thereby, a thin strip of phenol condensation productcarried by the magnet structure and an armature supported by said stripin cooperative relation to the magnet structure and winding.

5, In apparatus of the character disclosed,

a substantially horizontally disposed U -magnet, upwardly angledbrackets at the ends of said magnet, pole 'piecescarried by saidbrackets, a downwardly inclined armature bar in cooperative relation tosaid pole pieces,

'a' strip of resilient non-magnetic insulating material supportingsaidarmature bar in com-' ing strip of insulating-material securedsaidrelation and a ,winding surrounding the upper portion of saidarmaturebars 6. In an electro-magnetic phonogra h ickup, a magnet structure,"a m

porting said stylus bar in cooperating relation to "the -magnetstructure and a winding inductively associated with said stylus bar.

' 7.5.In. an electro-magnetic phonograph pickup, a magnet structurehaving pole pieces, a stylus ar havinga magnetic portion incooperative-relation to said pole pieces, a

agnetic sty us a er, a strip of sheet insulation resiliently s .pa

st'ri' offlexible sheet phenol condensation pro uct-material'resilientlysupport said stylus 'barand-a winding associated stylus bar. v v A v aIn an electricphonograph' pickup, comprising a 'U-magnet surted n flathorizontal relation, angled rackets extending from the ends of saidmagnet substantially C-shaped pole pieces supported by said brackets inspace opposing relation, a windpieces, a flat thin strip of sheetmaterial secured to'sald pole pieces and a short rigid straight armaturebar rigidly secured at one en 111g therefrom throu h the coil anpositioned betweent e spaced pole ieces, said armature bar having astylus soviet in i l'slofwerend 9. In apparatus of the characterdisclosed, the combination of a magnet and an electrically related.cooperatini vibrating member,

a flat sheet of thin flexi le insulating material, said vibrating memberbeing rigidly mounted on a portion of said fiat sheet material andsecuring means with another portion of said flat sheet material forsupport n the same with the vibrating member cam thereby in electricallycopperative relation with the'magnet.

10. In apparatus 0 the character disclosed,

said

ing mounted within the hollow of said pole to said strip and reject nterthe combination of a magnet structure, a strip of sheet insulation tosaid magnet structure,:a vibrating member carried by said strip ofinsulating material and operatively related to the magnet structure,said vibrat-- ing member projecting from one face of the insulatingstrip and having a stylus socket opening to the opposite face. of thestrip and a stylus clamp associated with said socket.

- 11. In apparatus of the character disclosed, the combination ofamagnet structure, a strip of sheet insulation to said magnet Ystructure and a vibrating member carried by said strip of insulatingmaterial and operatively related to the magnet structure, said Iinsulating strip having slots therein at opposite sides of the vibratingmember. I

12. As a new article of manufacture, a stylus mount for a phonographpickup, com

prising a flat strip of sheet insulating material and a stylus memberrigidly to 25 other member, a support for said vibrating an intermediateportion of said strip and projecting from oneface of the same.

13. As a new article of manufacture, a

stylus mount fora phonograph iiclcup, com- 5 prising a flat strip ofsheet insu atmg material and a stylus member rigldly secured to anintermediate portion of said strip and projecting from one face of thesame, said strip having openings therein at opposite m sides of thestylus member. 1

14. In apparatus of the character disclosed,

the combination of relatively movable electrically related members, oneof small mass and intended to vibrate with respect to the other member,a support for said vibrating member including a strip of sheetinsulation,

said vibrating member being rigidly secured to an intermediate portionof said strip and said strip being rigidly held at opposite sides ofsaid vibrating member.

' 15. In apparatus of he character disclosed,

the combination of relatively movable electrically related members, oneof small mass and intended to'vibrate with respect to the memberincluding a strip of sheet insulation said vibrating member beingrigidly secure to an intermediate ortion of said strip, said strip beingrigidly old at opposite sides of said vibrating member and thecross-sectional dimensions of said stri being reduced at points inbetween the vi rating member and the points at which said strip is held.

In testimony whereof I aflix my signature. as OLIVER B. PARKER.

